American telegraphy and encyclopedia of the telegraph; systems, apparatus, operation (1909)
Maver, William, jr. [from old catalog] · New York, Maver publishing company · leaf 214
176 AMERICAN TELEGRAPHY. R and R represent the resistance coils just referred to. In practice these coilsare generally termed the artificial line; sometimes the compensating line. The coil of the relay at either end Avhich is connected to the main line is termedthe main line coil; the coil…
Telegraph
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